extern void register_font_driver (struct font_driver *driver, FRAME_PTR f);
extern void free_font_driver_list (FRAME_PTR f);
extern Lisp_Object font_update_drivers (FRAME_PTR f, Lisp_Object list);
-extern Lisp_Object font_range (ptrdiff_t, ptrdiff_t *,
+extern Lisp_Object font_range (ptrdiff_t, ptrdiff_t, ptrdiff_t *,
struct window *, struct face *,
Lisp_Object);
extern void font_fill_lglyph_metrics (Lisp_Object, Lisp_Object);